From f03b94ef0e8792e06a0212912b1117f26cdc6dda Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Tue, 12 Dec 2017 09:43:43 -0800 Subject: pinctrl: rockchip: enable clock when reading pin direction register [ Upstream commit 5c9d8c4f6b8168738a26bcf288516cc3a0886810 ] We generally leave the GPIO clock disabled, unless an interrupt is requested or we're accessing IO registers. We forgot to do this for the ->get_direction() callback, which means we can sometimes [1] get incorrect results [2] from, e.g., /sys/kernel/debug/gpio. Enable the clock, so we get the right results! [1] Sometimes, because many systems have 1 or mor interrupt requested on each GPIO bank, so they always leave their clock on. [2] Incorrect, meaning the register returns 0, and so we interpret that as "input". Signed-off-by: Brian Norris Reviewed-by: Heiko Stuebner Signed-off-by: Linus Walleij Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/pinctrl/pinctrl-rockchip.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/pinctrl') diff --git a/drivers/pinctrl/pinctrl-rockchip.c b/drivers/pinctrl/pinctrl-rockchip.c index 49bf7dcb7ed8..f826793e972c 100644 --- a/drivers/pinctrl/pinctrl-rockchip.c +++ b/drivers/pinctrl/pinctrl-rockchip.c @@ -1278,8 +1278,16 @@ static int rockchip_gpio_get_direction(struct gpio_chip *chip, unsigned offset) { struct rockchip_pin_bank *bank = gpiochip_get_data(chip); u32 data; + int ret; + ret = clk_enable(bank->clk); + if (ret < 0) { + dev_err(bank->drvdata->dev, + "failed to enable clock for bank %s\n", bank->name); + return ret; + } data = readl_relaxed(bank->reg_base + GPIO_SWPORT_DDR); + clk_disable(bank->clk); return !(data & BIT(offset)); } -- cgit v1.2.3